Giovanni sfica



UNITE lPATES PATENT @EIQ.

GIOVANNI SPICA, OF VENICE, ITALY.

EXPLOSIVE AND METHOD or MANUF'Ac'rURmGsAME.

No Drawing.

To all whom it may concern Be it known that I, GIOVANNI SPICA, a subject of the King of Italy, residing at Venice, Italy, professor of chemistry, (whose post-oilice address is N 3341 Sant Antonino, Venice, Italy,) have invented certain new and useful Improvements in Explosives and Methods of Manufacturing Same, of which the following is a specification.

In a memorandum published last year (Att cZeZ Beale [still info c'nezo (ii Science, Lettm'e ecZ Arti, T. LXXI 1911/12, p. 782, and Zeizsch'rdft fiir alas Gescamte Scitiessprepared with collodion cotton and with 7 sufficient quantities of nitroglycerin, the solvent action of the latter is 'suflicient (when appropriate methods areadopted) to give adequate gelatinization, but where the collodion cotton isreplaced by 'guncotton the action of the nitroglycerin alone when present in limited quantities is no longer sutficient to produce good gelatinization, as is also the case when collodion cotton is used with only a relatively small quantity of nitroglycerin. Inv these latter cases the gelatinization is promoted by a solvent such as acetone which is added and which remains during the preparationof the powder, but isafterward as far as can be eliminated. As a consequence not only are traces of solvent necessarily left in the explosive causing variation in composition and ballistic propcities but the powder is obtained in a more or less porous condition harl nful'to' its keeping qualities. Such procedure remains unaltered when are used.

It has been ascertained that the introduction of phenanthrene into mixtures of nitro- Application filed June 4, 1914. Serial No. 842,847.

stabilizing or cooling agents Specification of Letters Patent. Patented Ai 15,1918.

glycerin andcollodion cotton can beeflected in the following Ways-: (a) by utilizing the property of the nitroglycerin to dissolve a certain proportion of phenanthrene at ordinary temperatures; (3)) by the use of a phena'nthrene solvent or of a solvent for the .phenanthrene and the nitroglycerin or collodion cotton, or both; (0) by mixing it directly with the pastes, utilizing in order to obtain homogeneity, its property of melting at a temperature of 9697 0. Under practical conditions however, the following question arises :The incorporation of the phenanthrene according to the first method besides presenting some danger in the dissolution when working with large quantities of nitroglycerin, has only a limited applicability as the phenanthrene is but slightly soluble in the nitroglycerin atordinary temperatures. This method is not, therefore, applicable in practice. The use of solvents according to the second method (7)) has the effect of yielding more or less porous powders, apt to favor chemical changes under external influences and therefore to reduce the life of the powder notwithstanding the beneficial influence of the phenanthrene. Taking into account this'and other inconveniences hitherto encountered in powders preparcchwvith solvents, this method also leaves much'to be desired. This leaves the third method referredto which, in fact, has

now been found to be most satisfactory; As"

the result of careful experiments it has. now been found that phenantlirene has the prop erty while melting of acting as a solvent in nitrocellulose and nitroglycerin mixtures and under the influence of warmth facilitates gelatinization and leads to satisfactory homogeneity in the product. As a result the employment ofthe stabilizer and cooling agent phenanthrene in such a way that it canexert its gelatinizing action allows of obtaining a stabilized explosive with a low percentage of nitroglycerin anda high per centage of collodion cotton and without the employment of a volatile soh'cnt.

The present invention consists in the manufacture of nitroccllMose-nitroglycerin explosives of this character by cmployu'ient of phenanthrene under suitable conditions and in explosives so produced.

This invention furthcrconsists-in the imby the use of the following proportions nitroglycerin 29.96, collodion cotton ".6423,

phenanthrene 6.05, 5 or in practice, nitro glycerin collodion cotton 64%, phena-n threne, 6%. The theoretical composition-of this mi-Xtureand of its decomposition prod nets are the following The following method of preparationis the one which should be adopted for powders with the ingredients in proportion Within the above limits: The phenanthrene bath keptat 40 to stirred in every direction by a current of, compressed air, is added, little by 1ittle,':' the' appropriate quantityof nitroglycerin; When the latter has permeated the whole is well mixed with the;-predetermined .quantity of almost dry collodion cotton, and to this mixture, which is sus ended in a water and continually mixture, the bulk f the wateri-s eliminated by filtration and the pasty mass allowed. to stand at a temperature above 10? (1 .for'8' to 10 days. The paste is next centrifuged to free it from a further quantity of water and then it is submitted to compression between the cylinders of a sheeting machine, which are internally heated by steam so as to reach at the external surface a temperature-of 100 to 105 C. The repeated flattening increases the density, eliminates the water, melts the phe'nanthrene and completes the gelatinization of the product, which is thus obtained as homogeneous, dry, transparent sheets devoid of blisters and of light color. These sheets kept at the thickness required, are while still somewhat warm cut by a special cutter into strips of the desired size for arms of different caliber. The powders thus prepared-are similar to ballistite, but are a little lighter in color and also a little more horny.

The composition'specified above gives a powder. with a density of 1.6. This one, which, according to calculation, for each kilogram should yield 1014 liters of gas and liberate 866 calories,'has 'ven when exprloded in-the Berthelot bomb 864 calories.

0 trace of nitric acid could be found. Exploded in the Vielle bomb in such quantity as to give an internal pressure of 2500 atmospheres, a corrosion value of 0.036 per gram was obtained. A stabilityltest at a temperature of C. in the silvered'vessel sho ed a ave age of 2800 hours, while;

shooting tests have demonstrated the greatest regularity in ballistic effects. 7

In order thatthe abovedata may 'beoon' trastednwithjresul ts upon other gelatinized explosives the'following tableis given 2- car Liters D 0 ,0 gas- 4 ura- AbsotiesdeetO" C. gg: bihty Kind of exlute veloped and at 'wder (sil- Observaplosive. denfrom 760mm. P er vered tions.

sity. 1 k given g test) in pow er. bylkg. 7' hours.

- 'powder.

B all is 1; its 1. 63 1250 810 0. 169 1 50 Made with- (50% of mp out soltrogly-cr A vent. erin). 4 v I Cordite M. 1.57 970 94-8 930 Made with y D. (30% of solvent.

' n itroglyc erin).' 1

Chilworth 1. 55 889 964 0. 063 2500 Made with ,powder.. solvent.

Powder t.60 1014 0.036 2800 abovedov scribed. I

.Thelprincipal advantage of the improved methods and products according to this in volitional-e it will beunderstood, as fol- -lows:(. l) The explosives can be convenjiently. manufactured without the help of volatile solvents and are quickly in conditionfor use. (2) They have a constant and definite composition and give ballistic effects of the greatest regularity. (3) They develop in explosion a small amount of heat. (4) That in explosion an extremely large volume of gases isgenerated. (5) That there is no. mtric acid among the products of explosion: (6) That corrosion in arm or weapon is reduced to a minimum. (7) That an extremely high figure is obtained in' the durability test at 80 C. in the silveredvessel. To this may be added the economic ad vantage, arising from the cost of manufa'cture of such powders being lower than that of powders manufactured with a volatile solvent. v

Having now fully described my said invention and'the manner in which the same is to be performed, what I claim and desire to be secu'redby Letters Patent of the United States is:

1. In the manufacture of smokeless powders of the character described, the herein described method which consists in mixing phenanthrene with a predetermined quantity of collodion cotton and putting the mass in awater bath. kept at a temperature of from 40 to 45 C., stirring the mixture with the water while adding gradually a quantity of nitroglycerin, then removing the excess of the water by filtration and allowing the still pasty mass to dry at a temperature above 10 0., then centrifuging the dried pasty mass to free it as much as possible from the rest of the'waten-and then compressing the o fcylmders wh ch are mean While heated from the inside by means of name to this specification in presence of two steam, as setl fprth. a 1 1 subscribing witnesses.

2. A smo e ess pow er of tie ciaracter L described consisting essentially of oollodion PROF GIOVANNI SPICA' 5 cotton, nitroglycerin and phenanthrene in or WVitnesses:

about in the proportions specified. GIOVANNI FAMARAT, In testimony whereof I have signed my POTTARI FRANcnsoA.

L'opies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

. Washington, D. 0. I 

